Apparatus for making rasp webs



Jan. 29, 1952 A. E. TOBEY 2,583,615

APPARATUS FOR MAKING RASP WEBS Filed Dec. 11, 1945 2 SHEETS-SHEET l INVENTOR. AL 70/ E. 7055): BY

Jan. 29, 1952 Filed Dec. 11, 1945 A. E. TOBEY APPARATUS FOR MAKING RASP WEBS 2 SHEETS-SHEET 2 VII 7 IQQVIIIIIIII llilllllllllh IIIIIII F'IELE INVENTOR.

ALTO/V E. TOBEY Patented Jan. 29, 1952 UNITED S TATES OFFICE 2,583,615 APPARATUS FOR MAKING RAs'P WEB's Alton E. Tobey, Santa- Cruz, Calif." Application December 11, 1945;Seria1Nor634,375 2'Claims. (Cl. 1--'-1) This invention relates to the construction of point-studdedwebsusedas rasps in roughing the surfaces of objects such as tire casings preparatoryto bonding a layer of material such as retread rubber thereto.

An object-of the invention is to provide apparatus for arranging: ajumbled mass of pointed abradingelements into: orderly relationship and for transferringthe arranged elements into engagementwithi aweb member designed as a permanent carrier therefor.

Another object of theinvention is to provide apparatus of the character described which elfects an orderly columnar arrangement or grouping zof point elements such as tacks and permits thetransferral of an arranged group between separated locations without disturbing the relationship between theelements of the group.

A further objectof the invention is to provide, in apparatus of thecharacter described, transfer means for carrying prearranged groups of pointed elements from an arranging stage of the apparatusto another stage of the'apparatus and, prior to returning the carrier to the arranging stage, for depositing the pointed elements in theirpredetermined arrangement.

Still another object of the invention is to provide, in apparatus of the character described, meansfor receiving successive-groups of point elements arranged in a predetermined pattern and for-maintaining the patternarrangement of said elements whilethe latter are "being engaged with a member functioning to maintain permanencyof pattern between the-respective elements.

The invention possesses other objects and features of advantage, some of which, with the foregoing will be set forth in the following. description of thepreferred form of the invention which is-illustrated in the drawings accompanyingiand formingpart of the specification. It is to be uning made by the said may be adopted within as set forth in the 'claimsl Refer-ring to the drawings:-

drawings and description Figure 'l is a top planview of the transfer plate loading machine.

the'view broken'away so as to more clearly disclose the internal" construction.

Figure" 3 is a top plan view, to an enlarged scale', of a portion of a transfer plate.

Figure .4 is a--verticalsectional view of the the scope of the invention a ders'tood; however, that variations in the show transfer plate taken in the plane'indicatedby' the line -4 of Figure 3.

Figure 5" is a plan View of a' transferplate" showingthe Iatt'er'in inverted'relationship' to the showing of Figure 3 and illustrating the plate in association with the pointed abradingelements. Portions of the view are broken away so as to compress it.

Figure 6 is a vertical sectional viewtaken in the plane indicatedby theline -6-6 of Figure 5.-

Figure 7"is a' vertical sectional View of the setting. die.

Figure 8 is a verticalisection'al view, similar to a portion-of Figure 7, sh'owi'n'g the arrangement" of the die prior to the insertion of" the pointed rasp elements in their mounting web;

Figure 9 is a view similar to Figure 8 showing the relation of Y the parts when the rasp. elements are fully engaged in the mountlngweb;

Figure IOis an enlarged plan view of a portion of a completed rasp section.-

Figure 11 is a vertical sectional view talgeninthe plane indicated by the line l l-ll of Fig ure- 10.

In the process of retreading automobile tires;

ower driven rotary rasps are employed for abrading from the tire carcass sufficient of the original tread'rubber to provide a suitable roughened" base to which the new camelback may be securely bonded. Such-rasps,- similar to that described in myprior application, Serial No. 546,82l, nowmatured into Patent No. 2,436,621 dated February. 24, 1948,. comprisea rotatabledrum-to which is afllxeda peripheral band carryingradi'ally outwardly protruding pointed abrasion elements in the nature of tacks which provide on the drum a multitude of raspteeth'which function,when a tire carcass is held against the revolvingdrum, totear and abrade the treadrubber from the carcass. Such rasp--bands-un der normal usage are-capable of remaining satistactorily sharp-r during the processing 7 of 1 about fifty carcasses which means that,- in a busy shop; a

several replacements per day of the rasp bands base band of thin sheet metal perforated at spaced-intervals in its surface to receive commontacks, have i been comparativelyexpensive to pro-'- duce and add considerably to'the costof machine operation.

I haveprovidedmechanism for cooperatively producing such rasp: bands which is 'not only-i-capable of increasedproduction over former methods; whichresults ina material savingto the con- "sumer,=but the tack mounting-is actuallycstronger are required- These rasps-which comprise a secured .to the Opposite ends of ashaft 52 e and will extend the useful life of the rasp. One of the major problems in the manufacture of rasps of the type above referred to is the placement of the tacks in the individual holes of the band and the handling of the tacks preceding the actual placement. In the apparatus of my invention I have reduced these former time-consuming steps to the status of ordinary rapidly accomplished components of the procedure. Figures land 2 I, have illustrated mechanism, for arrangin the tacks automatically in the grouping or pattern in which they are to ultimately appear in the rasp band, comprising a suitable frame having legs l2 on the upper ends of which is mounted an open top hopper l3 having a bottom M which slopes downwardly toward what will be referred to as the front of the machine to form a well 16 toward which objects such as tacks deposited on rearward portions of the hopper bottom [4 may flow under the influence of gravity. Thus the contents of the hopper will be concentrated at the front of the machine where they will be within easy reach of the operator whose working position is located at the said front end of the machine. Extending transversely across the hopper, at a position medially of the front and rear ends thereof is a rocker shaft I! which is mounted for rotary motion in bearings l8, carried on the respective sides of the hopper, and which is secured to rocker bars l9 movable with the shaft. ll and extending therefrom forwardly and rearwardly of the hopper. Shackle links 2| and 22, pivotally connected by bolts 23, to the respective ends of the rocker bars I9, rise vertically from the latter and are pivotally engaged, by means of screws 24 to the side members of a rectangular transfer plate frame 26 positioned in superposed relation above the hopper. The frame 26 is composed of angle bar or other structural material having an upwardly exposed rabbet 21 which forms in the frame a positioning ledge adapted to receive and position a plurality of transfer plates 28 which are cooperative, when in place, to form a relatively extended co-planar upper surface on the frame. These transfer plates which may be made about three inches wide are about twenty-six inches in length and represent the circumferential length of the rasp bands which are made to fit standard eight inch diameter rasp drums with which the rasp machines are provided.

Means are provided for moving the frame 26 and the transfer plates 28 carried thereby so as to impart to the latter an oscillating gyratory movement. Secured to and extending rearwardly from the frame 26 is a pair of ears 29 each of which is apertured to receive the pivot bolt 3| carried by a clevis 32 attached to one end of a link 33, a similar clevis 34 being secured to the other end of the link and being pivotally engaged by means of a bolt 36 in a selected one of a series of holes 31 formed in a lever 38 secured to and'rising from a shaft 39 journaled for rotary movement in bearings 4| mounted on and extending from the rear end of the hopper 13. Levers 42 secured to the opposite ends of the shaft 39 and extending forwardly of the machine each have a series of apertures 43 provided therein, a selected one of which may receive a bolt 44 carried by an end clevis 46 of a substantially vertical connecting rod 41 having an additional clevis 48 at its other end which is pivotally attached by means of a pin 49 to the distal ends of a crank 5|. The cranks 5| are tending transversely of the machine and journaled in bearings 53 which are mounted on suitable support members 54 erected on the cross-member portions 56 of the machine frame. The shaft 52 is fitted with a peripherally grooved pulley 5'! connected through a belt 58 with the drive pulley 59 which is carried and driven by a motor 61 carried by a base plate 62 suitably mounted on the machine frame structure. Current for operating the motor 6! may be supplied through a suitable length of extension cord, not shown, and means for controlling the operation of the motor may be provided in the form of a lever or pushbutton switch 63 mounted on the side of the hopper adjacent the operators work position and connected with the motor through a length of conductor cable 64. Energization of the motor 6| to rotate the shaft 52 will, through the connecting rod and bellcrank drive 41-42-38, cause oscillatory movement of the shaft 39 and will create a resulting oscillatory movement of the transfer plate frame.

the pins 36 and 44 to engage selected ones of the holes 3? and 43 in the respective levers 38 and 42. The arrangement of the parts is such that, during oscillation, the arcuate travel of the shackle links 2! and 22 will impart a slight vertical oscillatory movement to the frame 26 and the transfer plates mounted therein so that material, such as loose tacks, placed on the trans-- on the oscillating transfer plates. The arrangement of the pivoted rocker l9 permits the frame 26 and its contained transfer plates 28 to be rocked back and forth in a vertical direction, while the horizontal oscillation is in progress, by manually raising or lowering the forward side of the frame. Means are provided, however, for limiting the degree of rearward tipping so that the major discharge or clearing of surplus material-from the transfer plates may be directed toward the forward end of the plates into the well I5. This is accomplished by providing the rearmost end of each rocker bar 19 with a lug 55 drilled and tapped to receive a vertical screw 60 which impinges against and which may slide horizontally over pads 65 provided on the bottom of the hopper.

Means is provided in each transfer plate for trapping and holding, in a pattern or predetermined spaced relationship, a quantity of the a enough, as will be seen in Figure 6, to receive the 7 heads 68 of the tacks. Provided in the recesses is a plurality of holes 69 passing completely through the plate and having their lower ends provided with countersunk portions H. The diameter of each of the holes 69 is sufiicien'tlyin' excess of that of the shank of the tack 66 that the latter may pass freely into the hole without any danger of binding therein and the counter- The degree of suchmovement may be varied as desired by moving aaaegem:

sunk portion." iofieach; hole is provided so as to shorten the sides of the, hole at its upper or.

face bearing a multitude ofperforations which,

when a quantity of loose tacks is placedthereon and the frame isoscillated and rocked as explained above, will serveas traps into Whichindividualtacks will fall, point foremost, the tacks coming to rest with their heads resting in the recesses 67 and substantially flush with the plate surface. Complete occupancy of all of the holes by tacks will take only a comparatively short time whereupon the transfer plates are ready for removal from the machine.

The next step in the procedure is to transfer bodily the groups of tacks in each transfer plate into a die illustrated in Figure 7 which effects simultaneous connection of the tanks with the band forming the base member of the rasp. The die comprises a base plate 72 on which is mounted by suitable spaced screws 73 a lower holder plate 74 which carries in apertures '16, positioned and spaced correspondingly with the holes 69 of the transfer plates 28, punches l! which rise upwardly and slidably engage in mating holes i8 provided in an upper die plate 19 overlying and vertically registered with the base plate 12 and the punch holder plate 14. The punches Tl, it will be observed, are provided with shouldered extensions 8! which pass through the apertures 76 and are provided with peripheral grooves 82 coincident with the bottom surface of the plate 74 inwhich wire snap rings 83 or the like are engaged for securing the punches to the plate 14. Springs 84 are interposed between the punch holder plate 14 and the upper die plate 19 to urge the latter upwardly and screws 86 concentric with the springs, threadedly engaged in the upper die plate and slidably engaged in suitable apertures and a counterbore 87 in the punch holder and base plates respectively, limit the upward movement of the upper die plate relative to the punches ll so that the upper portion of each hole 18 in conjunction with the upper end of each punch provides an upwardly opening recess 88 the upper surface of the die plate 19. A backing plate 89, shown in Figures 8 and 9, is adapted to overlie the upper die plate and is provided with apertures 9i axially registered with the recesses 88. The die so far described is adapted for operation by a standard punch press or other such mechanism which will function to cause cycling movement of the die plate 19 toward and from the base plate 12.

Before a transfer plate is removed from the tack distributing machine a strip 92 of sheet metal, shown in Figure 6 and large enough to completely cover the surface of the transfer plate is laid over the plate and is held in contact therewith manually or by other suitable means while the transfer plate is being inverted. This strip 92 then underlies the heads of the tacks and prevents the latter from falling out of their respective locating holes 69. The inverted transfer plate, together with its underlying strip 92 is then laid upon the upper surface of the die plate 19 in the same relationship as though the structure of Figure 6 were lowered until it rested on the upper surface of the structure of Figure '7. This will position the tacks 66 with their points uppermost directly above the recesses 88 of the; dieuplate 19 so" thatxby manually withdrawing-the strip 921 from be'--- tween the marginally registered plates: 28 and: it. the tacksmay'be permitted to fall into the recesses 88 until their heads: 68 rest on theupper" after which the emptied,

ends of thepunches l1 transfer'plate is returned to the tack distributing machine for reloading, On the upper surface of the die plate. 191 is now laid a blankstrip 93 of'sheet metal astshown in Figure 8 and this strip is overlaid by the backing plate 819 after which the punch press or other such mechanism is operated to suddenly andforcibly bring the upper dieplates 19- toward the .basevplate 12. This, as

shown in Figure 9, will cause the points of.the

respective tacks to pierce the sheet 93 and to mushroom therethrough as indicated until the tack head engages the sheet. This radial expansion of each perforation by the tapered shank of the tack will result, after the tack has been finally positioned, in a reactionary radial pressure of the displaced sheet metal on the body of the tack which will serve to securely bind the latter to the sheet. In addition, the protruded metal will form a comparatively elongated bearing axially f the tack shank which will further serve to lend rigidity to the mounting and will delay the loosening of the tacks which the rasping action will eventually cause. Sections of finished rasp strip are illustrated in Figures 10 and 11.

From the foregoing description it will be seen that various steps of producing spiked plates or strips, especially the heretofore difficult and time-consuming steps of arranging the barbs or tacks in their pre-arranged pattern and in finally affixing the tacks to the base plate or strip have been reduced to very simple and rapidly accomplished procedures, and that the resulting product as regards its durability is superior to the heretofore known types of machine rasps.

I claim:

1. Apparatus of the character described for driving tacks into a strip of metal of a thickness less than the tangs of the tacks, a die, said die comprising an upper plate, a base plate and a backing plate, said upper plate having a plurality of apertures therein, punch members extending from said base plate into said apertures and having upper surfaces normally below the upper surface of said upper plate and arranged to receive and support tacks in point-up position, means on said upper die plate for supporting and receiving said metal strip, said backing plate having apertures therein arranged in complementary pattern relationship with said upper plate apertures, said backing plate apertures being of a cross-sectional area less than that of said upper plate apertures, said backing plate disposed adjacent said metal strip, said upper plate, metal strip, and backing plate being movable relative to said base plate whereby said tangs will pass entirely through said strip and enter said backing plate apertures.

2. Apparatus of the character described for driving tacks into a strip of metal of a thickness less than the length of the tangs of the tacks, a die, said die comprising a base plate, an upper plate and a backing plate, said upper plate hav ing a plurality of apertures therein, means within said apertures and fixedly mounted relative to said base plate for receiving and supporting said tacks in point end up position, means on said upper die plate for supporting and receiving said metal strip, said backing plate having apertures therein arranged in complementary pattern relationship with said upper plate apertures, said backing plate apertures being or a cross-sectional area less than that of said upper plate apertures, said backing plate disposed adjacent said metal strip, said upper plate, metal strip, and backing plate being movable relative to said base plate whereby said tangs pass entirely through said strip into said backing plate apertures to effect formation of a receiving aperture for said tangs.

ALTON E. TOBEY.

- REFERENCES CITED 'UNITED STATES PATENT 7 Number Number Name Date Bapterosses Sept. 13, 1884 Ross May 20, 1890 Estabrook July 14, 1896 Van Doren Apr. 10, 1923 Cocozella Feb. 2, 1937' Standish Nov. 7, 1939 FOREIGN PATENTS Country Date Great Britain Oct. 10, 1884 

